Minimally invasive fusion surgery for patients with degenerative spondylolisthesis and severe lumbar spinal stenosis: a comparative study between MIDLIF and TLIF.

PURPOSE: This study aims to compare midline lumbar interbody fusion (MIDLIF) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for treatment of patients with severe stenosis and lumbar degenerative spondylolisthesis (DS), focusing on dural tears rates, other complications, clinical and radiological outcomes. METHODS: This cohort study included patients with severe lumbar spinal stenosis (Shizas C or D) and lumbar DS who underwent MIDLIF or MIS-TLIF. Propensity score matching was done and the groups were compared regarding surgery time, length of stay, perioperative complications, clinical results and radiological outcomes, at 1 year of follow-up. RESULTS: The study included initially 80 patients, and 72 patients after matching, 36 in each group. Six patients had dural tears, four in the MIDLIF group and two in the MIS-TLIF group (p = 0.67). General complication rates and reoperations were not significantly different between the groups. Good or excellent clinical was achieved in 75% of the MIDLIF patients and 72% of the MIS-TLIF patients (p = 0.91). Radiological parameters showed small but statistically significant (p < 0.01) improvements after surgery, particularly in segmental lordosis and lumbar lordosis (2.0° and 1.7°), while pelvic tilt and global tilt decreased (1.6° and 2.6°). These findings were similar for both groups. CONCLUSION: Our study confirms that MIDLIF is a safe and reliable minimally invasive alternative for lumbar interbody fusion in DS, even in patients with severe stenosis and previous spine surgery. It seems to offer similar results to MIS-TLIF regarding clinical results, radiological outcomes and complications.

Are the results of patient reported outcome measures after spine surgery influenced by recall of preoperative scores? A randomized controlled trial.

BACKGROUND CONTEXT: Patient reported outcome measures (PROMs) are of utmost importance to clinical practice as they permit a patient-focused evaluation of surgical outcomes. However, recall bias can limit an adequate interpretation of PROMs. PURPOSE: To assess the impact of recall bias of preoperative status on postoperative PROMs of patients submitted to surgery due to degenerative spine disease. STUDY DESIGN / SETTING: Randomized controlled trial in a tertiary care neurosurgical unit in Portugal PATIENT SAMPLE: All patients submitted to surgery at our institution from January 2019 to April 2020 due to degenerative lumbar or cervical spine disease with valid PROMs questionnaires were enrolled, and 2 computer generated randomized groups were created. OUTCOME MEASURES: The study´s primary endpoint was the median postoperative Core Outcome Measure Index (COMI) score. METHODS: The intervention group was sent postoperative questionnaires including preoperative answers, while patients in the control group were sent the same PROMs without the preoperative answers. RESULTS: Randomization was applied to 236 patients (118 for each group) and valid results were obtained for 147 patients (81 lumbar, 44 from the intervention group; and 66 cervical, 29 from the intervention group), from which 88 (60%) were females, with a median age of 58 years. Both groups shared similar baseline clinical characteristics and preoperative scores. Median postoperative COMI scores and interquartile ranges (IQR) were 4.20 (IQR: 2.30-6.00) and 5.45 (IQR: 3.75-7.40) for the intervention and control groups, respectively (Wilcoxon, p=.02). This difference was reached mainly due to cervical spine patients as median postoperative COMI score was 3.95 (IQR: 2.20-5.32) in the intervention group and 5.1 (IQR: 4.0-8.4) in the control group (Wilcoxon, p=.01). No significant difference was reached for lumbar patients. CONCLUSIONS: Better PROMs scores were obtained for degenerative cervical spine patients to whom the preoperative results were provided. Therefore, providing preoperative scores to patients upon postoperative PROMs fulfilment might influence postoperative results. Further research is necessary to increase the reliability of PROMs in clinical practice.

How accurate is fluoroscopy-guided percutaneous pedicle screw placement in minimally invasive TLIF?

INTRODUCTION: The accuracy of pedicle screws placement has been the subject of many studies and varied rates of screw malposition have been reported. This study evaluates the placement of pedicle screw inserted percutaneously, guided by intraoperative 2D fluoroscopy, in minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF). METHODS: Retrospective study of patients who underwent MIS-TLIF from 2007 to 2016 in a single center, for degenerative pathology. All patients had a follow-up lumbar CT scan one year after surgery to evaluate pedicle violation, location and degree. Gertzbein classification was used for description of the degree of violation. RESULTS: This study included 241 patients, with a mean age of 57 years (SD 11.69). A total of 1045 screws were evaluated. Most patients were fused at L4-L5 or L5-S1 levels. The total rate of pedicle walls' violation was 13.97%, however only 4.31% of the screws presented violations exceeding 2 mm. Only 5 patients were reoperated because of complaints related to screw malposition (0.48% of all screws). There was a trend for an increased rate of pedicle violation for upper lumbar pedicles (p < 0.001). For S1 screws, violations were more common on left pedicle screws (17.89% vs 7.53%, p = 0.03), with an Odds Ratio of 2.68 (95% CI: 1.07-6.80). CONCLUSION: Percutaneous pedicle screw insertion guided by intraoperative 2 D fluoroscopy in MIS-TLIF is safe and most of pedicle violations seem to be minor and without clinical consequences. In S1 screws, the surgeon's side was more prone to violation.

Correlation between clinical outcomes and spinopelvic parameters in patients with lumbar stenosis undergoing decompression surgery.

PURPOSE: The aim of this study is to determine if there is a relation between preoperative sagittal alignment, based on radiographic parameters, and clinical outcomes, after lumbar decompressive procedures, in patients with lumbar spinal stenosis (LSS). METHODS: This study enrolled patients with LSS who underwent lumbar decompressive procedures, between January 2016 and December 2017. Preoperative spinopelvic parameters were measured, and patients were divided into radiological groups according to the median of the following variables: relative lumbar lordosis (measured minus ideal lumbar lordosis), relative pelvic tilt (measured minus ideal pelvic tilt) and sagittal vertical axis (SVA). Clinical outcomes were compared between these groups and included the Core Outcome Measures Index, EuroQoL Five Dimension Questionnaire (EQ-5D) and Oswestry Disability Index (ODI) scores before and 1 year after surgery. Further correlation statistics between sagittal radiological measurements and the postoperative outcome scores were performed. RESULTS: The study included 104 patients. We did not find any clinically important difference in clinical outcomes between radiological groups. However, in correlation analyses we found a significant but weak statistical correlation between relative lumbar lordosis and both preoperative and postoperative ODI, as well as a significant statistical negative correlation between SVA and postoperative EQ-5D. CONCLUSION: Preoperative spinopelvic parameters did not significantly correlate with clinical outcomes after decompression surgery for LSS on non-deformity patients. Patients had a comparable improvement after surgery, regardless of their preoperative sagittal alignment.

Treatment of old cervical bilateral facet dislocation: Case report and literature review.

Late diagnosis of cervical bilateral facet dislocation is rare and contributes to concerns in the management of these patients. We present a case of a 44-year-old woman presented 8 months after a trauma with persistent neck pain, without neurological deficits. A bilateral C5-C6 facet dislocation was identified. The patient was treated with a combined C5-C6 approach: posterior facet joints release, anterior discectomy and fusion, bilateral posterior fixation. Surgery was performed under intraoperative neurophysiological monitoring. The postoperative period was uneventful, and the patient presented functional improvement. Late surgical treatment of bilateral cervical facet dislocation is safe and feasible. Combined procedures are needed for proper reduction and stabilization of the spine. Intraoperative neurophysiological monitoring adds value to this technique contributing to good outcomes.

Midline lumbar interbody fusion (MIDLIF) with cortical screws: initial experience and learning curve.

BACKGROUND: A variety of surgical techniques can be used to achieve lumbar spinal fusion for management of degenerative conditions. Transforaminal lumbar interbody fusion (TLIF) is the most popular technique; however, midline lumbar interbody fusion (MIDLIF) is a valid alternative to the more traditional pedicle screw trajectory with potential advantages. The aim of this study is to evaluate the clinical outcomes from a cohort of patients submitted to MIDLIF in a single hospital during the surgical team's initial learning period. METHODS: The first 30 consecutive patients who underwent single- or two-level MIDLIF surgery for lumbar degenerative disease were included in this retrospective study. Patients' demographics, surgical data, length of hospitalisation, and perioperative complications were analysed. Preoperative and postoperative radiographic parameters were obtained. Validated questionnaires, Core Outcome Measure Index for the back, Euro-QoL 5-Dimensional Questionnaire, and Oswestry Disability Index, were used for clinical assessment. RESULTS: Mean surgery time was 278.53 ± 82.16 min and mean hospitalisation time was 6.17 ± 3.51 days. Six patients experienced complications, four of which being dural tears with no consequences, and two required reoperations during the mean follow-up of 25.23 ± 9.74 months. Preoperative and postoperative radiological parameters did not demonstrate significant differences. All clinical parameters significantly improved after surgery (p < 0.001). A complexity score was developed to more accurately compare the different procedures, and it strongly correlated with surgery duration (r = 0.719, p < 0.001). Furthermore, a moderate correlation was found between a developed Duration Index and the patient's order number (r = - 0.539, p = 0.002). CONCLUSIONS: In our initial experience, MIDLIF showed to be effective in significantly improving the patients' functional status, pain scores, and quality of life. The technique seems safe, with an acceptably low complication rate. Hence, MIDLIF can be considered as a promising alternative to more traditional TLIF and PLIF techniques even at the beginning of the learning curve.

Can We Assess the Success of Surgery for Degenerative Spinal Diseases Using Patients' Recall of Their Preoperative Status?

BACKGROUND: Patients' recall of their preoperative status is seldom used to assess surgical outcomes because of concerns about inaccuracy and bias. The present study aimed to measure the significance of this recall bias and its repercussion on patients' recollection of their preoperative status. METHODS: Patients submitted to surgery due to degenerative spine diseases over a 1-year period (n = 198) were included in this study. Each patient completed the EuroQol Five-Dimensional Questionnaire (including a visual analog scale), Core Outcome Measures Index (COMI) for neck (including neck pain and shoulder/arm pain numeric rating scale [NRS]), COMI back (including back pain and buttock/leg pain NRS), Neck Disability Index, and Oswestry Disability Index preoperatively. At 1 year after surgery, the patients were asked to complete 2 sets of the same questionnaires, one set regarding their postoperative status and the other set regarding their recall of their preoperative status. RESULTS: There was poor to moderate agreement between recalled and collected preoperative scores for all patient-reported outcome measures. Patients' recollection of their preoperative status was accurate for patients who underwent cervical spine surgery, but not for those who underwent lumbar spine surgery. Patients satisfied with the outcome after lumbar spine surgery recalled significantly worse scores compared with the actual preoperative scores. CONCLUSIONS: Using patients' recall of their preoperative status may lead to overestimation of the effectiveness of surgery, particularly for lumbar spine surgery. The self-assessed effectiveness of surgery interferes with the recollection of baseline status.

Age-Correlated Phenotypic Alterations in Cells Isolated From Human Degenerated Intervertebral Discs With Contained Hernias.

STUDY DESIGN: Human intervertebral disc (hIVD) cells were isolated from 41 surgically excised samples and assessed for their phenotypic alterations with age. OBJECTIVE: Toward the design of novel anti-aging strategies to overcome degenerative disc disease (DDD), we investigated age-correlated phenotypic alterations that occur on primary hIVD cells. SUMMARY OF BACKGROUND DATA: Although regenerative medicine holds great hope, much is still to be unveiled on IVD cell biology and its intrinsic signaling pathways, which can lead the way to successful therapies for IDD. A greater focus on age-related phenotypic changes at the cell level would contribute to establish more effective anti-aging/degeneration targets. METHODS: The study was subdivided in four main steps: i) optimization of primary cells isolation technique; ii) high-throughput cell morphology analysis, by imaging flow cytometry (FC) and subsequent validation by histological analysis; iii) analysis of progenitor cell surface markers expression, by conventional FC; and iv) statistical analysis and correlation of cells morphology and phenotype with donor age. RESULTS: Three subsets of cells were identified on the basis of their diameter: small cell (SC), large cell (LC), and super LC (SLC). The frequency of SCs decreased nearly 50% with age, whereas that of LCs increased nearly 30%. Interestingly, the increased cells size was due to an enlargement of the pericellular matrix (PCM). Moreover, the expression pattern for CD90 and CD73 was a reflexion of age, where older individuals show reduced frequencies of positive cells for those markers. Nevertheless, the elevated percentages of primary positive cells for the mesenchymal stem cells (MSCs) marker CD146 found, even in some older donors, refreshed hope for the hypothetical activation of the self-renewal potential of the IVD. CONCLUSION: These findings highlight the remarkable morphological alterations that occur on hIVD cells with aging and degeneration, while reinforcing previous reports on the gradual disappearance of an endogenous progenitor cell population. LEVEL OF EVIDENCE: N/A.

Anatomical variations of the vein of Labbé: an angiographic study.

PURPOSE: Little attention has been paid to the superficial anastomotic veins but severe post-operative complications can be related to iatrogenic venous damage. The importance of the position of VL (vein of Labbé) relates with the lateral accesses to skull base and medial tentorial lesions by posterior temporal approaches. The aim of this study was to characterize and deepen knowledge on the VL anatomy. METHODS: We reviewed retrospectively 101 hemispheres from cerebral angiographic studies in 59 patients (42 patients with bilateral angiography). RESULTS: VL duplication was found in 13 patients (31 %) and it was predominant on the left side. The absence of VL was rare (3 of 101 hemispheres). The mean location of the VL entry point in the transverse sinus was almost the middle of the distance between the inion and external acoustic meatus. The mean angle for this entry point was 69°. The mean VL caliber for the patients studied was 3.2 mm. Regarding the relation between VL and vein of Trolard, we found VL dominance in 31 % of the cases. About left-right intrapersonal variability we found a tendency for left VL dominance. CONCLUSIONS: We emphasized not only the interindividual differences but also the great intrapersonal variability of VL anatomy. The adequate study of the cerebral venous system particularities is of crucial importance for pre-operative planning to avoid severe complications.

Trans-lamina terminalis approach for third ventricle and suprasellar tumours.

BACKGROUND: The trans-lamina terminalis (TLT) approach to the suprasellar region and third ventricle is complex, with risks of visual and hormonal deficits. However, the postoperative deficits might not be directly related to opening of the lamina terminalis but to the close relationship of tumours with vital neural and vascular structures. The analysis of results using this approach was the objective of this study. MATERIAL AND METHODS: The TLT approach was used in 29 patients (18 craniopharyngiomas, 5 astrocytomas, 5 germinomas and 1 ganglioglioma). The extent of tumour removal, mortality and morbidity (especially visual or hormonal deficits) were studied. RESULTS: Complete tumour removal was achieved in 15 patients, subtotal extensive removal (more than 90%) in 9 cases and partial removal in 5 cases. Panhypopituitarism developed in 22 patients. Total tumour removal was associated with the development of endocrinological disturbances. There was worsening or the onset of new visual field defects in 4 cases. Postoperative endocrine and visual deficits were in the range generally described regarding surgery for tumours in this region. CONCLUSION: The TLT approach allows for extensive removal of third ventricle and suprasellar tumours, without increased risks of visual and hormonal deficits, compared to those described regarding surgery for lesions in this region.

The infratentorial supracerebellar approach in surgery of lesions of the pineal region.

BACKGROUND: Surgery of pineal region lesions is considered a challenging task, due to the particular relationship of lesions in this location with neural and vascular structures. Few series with a significant experience of dealing with these patients have been reported. METHODS: We review our experience using infratentorial supracerebellar approach in the surgery of pineal region, regarding the extension of the removal, postoperative morbidity, and discussing details of the surgical technique. In all cases, a supracerebellar infratentorial approach was used in the semi sitting position. RESULTS: A total of 32 patients were operated in the past 20 years (3 germinomas, 3 teratoma, 3 pineocitoma, 2 pineal tumor of intermediate differentiation, 6 pineoblastomas, 6 low grade astrocytoma, 2 glioblastoma, 2 metastasis, 1 ependymoma, 1 epidermoid tumor, 1 cavernoma, and 2 arachnoid cyst). Total removal was achieved in 15 cases and subtotal extensive removal in 7 patients. In the remaining cases, only partial removal was possible, due to the involved pathological types. There was no surgical mortality and no cases of cerebellar venous infarction. Morbidity consisted of transient ocular movement disturbance in 14 patients, transient ataxia in 3 patients, and 1 case of local cerebrospinal fluid (CSF) fistula with meningitis that required surgical treatment. CONCLUSION: Supracerebellar infratentorial is a safe approach to lesions in the pineal region, and total or extensive subtotal removal is possible in most cases, with acceptable morbidity.

Correcção de escoliose lombar degenerativa por técnica minimamente invasiva / Correction of degenerative lumbar scoliosis by minimally invasive technique / Corrección de escoliosis lumbar degenerativa por técnica mínimamente invasiva

A terapêutica cirúrgica da escoliose degenerativa consiste habitualmente em instrumentações e fusões mais ou menos extensas e associa-se a morbilidade significativa. A evolução tecnológica tem aberto caminho a técnicas menos invasivas que permitem obter resultados sobreponíveis aos das técnicas tradicionais minimizando a agressão cirúrgica. Descreve-se o caso de uma paciente do sexo feminino, de 63 anos, submetida a descompressão lombar posterior, em Janeiro de 2009, por alterações degenerativas marcadas. Poucos meses após a cirurgia a paciente referiu aumento das lombalgias e ciatalgia direita. O estudo imagiológico demonstrou agravamento de escoliose degenerativa L2-L5 associada a extrusão discal L2-L3 direita calcificada, fractura bilateral dos pedículos de L3 e espondilolistese degenerativa grau 1 L5-S1. Foi submetida a reintervenção cirúrgica por técnica minimamente invasiva consistindo em TLIF's L2-L3, L3-L4, L4-L5 e L5-S1 e fixação transpedicular L2-S1 bilateral, com correcção da deformidade no plano sagital e coronal. O caso clínico apresentado ilustra o potencial das abordagens minimamente invasivas no tratamento cirúrgico de escolioses degenerativas, devendo ser uma opção sempre presente considerando os benefícios potenciais para o paciente.

Surgical treatment of degenerative scoliosis usually consists of more or less extensive instrumentation and fusion and is associated with significant morbidity. Technological developments have opened the way for less invasive techniques which allow obtaining results comparable to traditional techniques, minimizing surgical trauma. In this work, we describe the case of a 63-year-old female patient who underwent posterior lumbar decompression, in January 2009, due to marked degenerative changes. A few months after surgery the patient reported increased back pain and right sciatica. Imaging studies showed exacerbation of L2-L5 degenerative scoliosis associated with L2-L3 right calcified disc extrusion, bilateral fracture of the pedicles of L3 and L5-S1 grade 1 degenerative spondylolisthesis. She underwent another surgery by minimally invasive technique with TLIF of L2-L3, L3-L4, L4-L5 and L5-S1 and bilateral L2-S1 transpedicular fixation with correction of deformity in sagittal and coronal planes. This case report illustrates the potential of minimally invasive approaches in the surgical treatment of degenerative scoliosis and should always be an option considering the benefits to the patient.

El tratamiento quirúrgico de la escoliosis degenerativa consiste habitualmente en instrumentaciones y fusiones más o menos extensas, asociadas a morbilidad significativa. La evolución tecnológica ha abierto el camino para técnicas menos invasivas que permiten obtener resultados comparables a los de las técnicas tradicionales, minimizando el trauma de la cirugía. Presentamos el caso de paciente de sexo femenino, de 63 años de edad, sometida a descompresión lumbar posterior en enero de 2009, debido a marcadas alteraciones degenerativas. Pocos meses después del procedimiento, la paciente refirió agravamiento de la lumbalgia y ciática derecha. El estudio de imágenes mostró empeoramiento de la escoliosis degenerativa L2-L5 asociada a extrusión discal L2-L3 derecha calcificada, fractura bilateral de los pedículos de L3 y espondilolistesis degenerativa grado I L5-S1. Fue sometida a la reintervención quirúrgica utilizando una técnica mínimamente invasiva que consistió en TLIF L2-L3, L3-L4, L4-L5 y L5-S1 y fijación transpedicular L2-S1 bilateral, con corrección de la deformidad en los planos sagital y coronal. El caso clínico que presentamos ilustra el potencial de los enfoques mínimamente invasivos en el tratamiento quirúrgico de las escoliosis degenerativas, debiendo ser una opción siempre presente cuando se consideran los beneficios para el paciente.